Joint NRAO and GBO Telescope Time Allocation Process

Proposals to the National Radio Astronomy Observatory (NRAO) and the Green Bank Observatory (GBO) for the scientific use of its telescopes are evaluated on the basis of scientific merit and technical feasibility using a panel-based proposal review system.  This joint process is run by the NRAO in accordance with it’s policy of non-discrimination and inclusion.

The NRAO 2021A Call for Proposals is for observations with the VLA and VLBA/HSA/GMVA; the corresponding call for the GBT can be found at the GBO Call for Proposals.

Extra-Large Proposals

In the 20A call for proposals, the NRAO invited the submission of Extra-Large proposals, defined as those requesting a total of more than 1000 hours of telescope time and/or extending over four or more observing semesters.  One VLA Extra-Large proposal is currently in its final review stage. If approved, about 250 hours of time will be allocated in the LST range 19 to 06 hours in the C configuration. There will not be an impact from this proposal on the available time in D configuration in the 21A semester.

It was also noted in the 20B call that "the maximum amount of time that can be requested through a Large proposal will be capped at 1000 hours starting from Semester 2020B."  Upon further review Large proposals will not be capped at 1000 hours starting in semester 20B.  Such proposals may provide us with some flexibility in scheduling (e.g., fill an underused LST range).

As a general rule at least 50% of the open skies time will still be available to the Regular, Triggered, and Large proposals that request time in this 21A call for proposals.

Continuing Opportunities

Extra NRAO Staff Help for VLBA Observation Setup and Data Reduction

NRAO is now offering extra staff assistance with VLBA observational setup and data reduction for new or novice users.  See the VLBA, HSA, and GMVA Proposal Guide page for details.

Joint Observing program

Access to the Joint Observing program will continue for the VLA, VLBA and GBT for semester 21A.  This includes joint observations with the XMM-Newton Project, the Chandra X-ray Observatory, the Hubble Space Telescope (HST), the Swift Gamma-Ray Burst Mission, and the Fermi Gamma-ray Space Telescope.  For more details see the Joint Proposal page.

Director's Discretionary Time Including Education and Public Outreach

Proposals for Director's Discretionary Time (DDT) may be submitted at any time. They must be submitted through the PST. DDT proposals are intended to address targets of opportunity, high-risk/high-return exploratory time, or other science opportunities deemed sufficiently urgent to justify prompt action. 

DDT proposals may also be submitted for the purpose of education and public outreach - for example, to image an iconic source or to support an educational opportunity for students. Such proposals should clearly justify the requirements for the requested time allocation and observing mode on any given instrument, and should describe the anticipated impact of the observation.  

While there is not an a priori limit to time that can be requested via DDT, it is expected that no more than 5% of the observing time on each telescope will be allocated for this purpose.

Other Proposal Opportunities

The NRAO would like to make users aware that there are additional proposal opportunities as follows:

• High Risk Proposals: As a means of maximizing its scientific impact through cutting-edge observations, the Observatory encourages the submission of high-risk/high-reward proposals.
• Commensal Observing: NRAO telescopes and backends are sufficiently flexible in many cases to allow two experiments to run commensally. To the degree that this enhances science return from the telescopes, NRAO wishes to support commensal projects subject to resource and scheduling constraints. 
• Filler Programs: Some programs are not time critical, strongly dependent on array configuration, or require highly subscribed LST ranges. Such programs may be able to take advantage of "filler" time.  

Further information about each of these programs can be found on the Proposal Opportunities page.